.select_express {
    .btn {
        margin-bottom: 0.6rem;
        margin-right: 0.4rem;
        width: calc(25% - 0.3rem);
        font-size: 0.7rem;
        white-space: nowrap;
        border-radius: 0.1rem;
        padding: 0;
        &:nth-child(4n) {
            margin-right: 0;
        }
    }
}